The present invention relates to a wrench which has a box end with an elongated space in the box end and an object can be respectively engaged with the elongated space at two extreme positions so as to be rotated clockwise and counter clockwise without removing the wrench from the object.
A conventional wrench 10 is shown in FIG. 8 and includes an open end which includes two jaws 11, 110 and a recess is defined in a throat portion between the two jaws 11, 110. The two jaws 11, 110 are designed to engage a hexagonal object 12. Another conventional wrench 100 is shown in FIG. 9 and has an open end and a box end which has a space 13 defined in the box end. A special designed inner periphery of the space 13 can engage a hexagonal object. As shown in FIG. 10, the two conventional wrenches 10, 100 allow the box end and the open end to tighten the object 12 repeatedly because of the recess which allows a corner of the object 12 being received therein while the wrench 10/100 returns to its original position. Therefore, the wrench 10/100 can tighten the object 12 without removing the open end or the box end from the object 12 and aiming the object 12 again. However, this feature is applicable only in one direction, in other words, if the object 12 is to be loosened, the open end/box end of the wrench 10/100 has to be turn to the other side and engages the object 12 again.
The present invention intends to provide a wrench having a box end wherein the object is engaged at a first position in the space of the box end when rotating clockwise, and the object is engaged at a second position in the space when rotating counter clockwise.
In accordance with one aspect of the present invention, there is provided a wrench and comprising a shank with a box end connected thereto. An elongated space is defined by a periphery in the box end and the elongated space comprises a first long side, a second long side and two short sides which are connected between the two first long side and the second long side. The periphery defining the elongated space comprises two identical portions which are symmetrical about an axis P which passes through a mediate point on the first long side and a mediate point on the second long side. Each portion of the elongated space comprises a substantial U-shaped cavity which includes one short side, a half first long side and a half second long side. Each short side has a first recess and a first engaging surface which connects an end of a periphery defining the first recess. The half first long side has a second engaging surface and a notch connected between the first engaging surface and the second engaging surface. An end of a periphery defining a second recess connects the second engaging surface. The half second long side has a third engaging surface which connects the other end of the periphery defining the first recess.
The primary object of the present invention is to provide a box end wrench that has an elongated space for a hexagonal object being engaged with two positions in the space. One position allows the object to be tightened and the other position allows the object to be loosened.
These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention.